(3x²-2)-(4x²-2x-3)+(2x-3)+(2x²-1)其中x= -1

问题描述:

(3x²-2)-(4x²-2x-3)+(2x-3)+(2x²-1)其中x= -1

(3x²-2)-(4x²-2x-3)+(2x-3)+(2x²-1)
=3x²-2-4x²+2x+3+2x-3+2x²-1
=x²+4x-3
=(-1)²-1×4-3
=-6